Can't Choose HTML on Q&A, Default text is white (on white!)

Howdy – quick one hopefully on the excellent Q&A plugin. Using an earlier CSS tweak provided by Mason, I've managed to get my sidebar displaying alongside the Q&A plugin, however, the plugin won't let me change between Visual and HTML editor. Also the TinyMCE editor doesn't appear. Another issue is that the default text is white (on a white background!) Can anyone spot the flaw?

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